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Ostrava weather by month: averages, rainfall & climate trends

Seasons run to extremes in Ostrava: monthly means span 20.6°C between the coldest month and the warmest. Rainfall leans toward the stretch from May to September. Ostrava weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+9.2°Chigh well above average

22° / 8°Today
12° / 5°Average
see today in detail →

How it's changed

+2.8°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4965frost days a year now (2016–2025) · 114 in the 1940sfrost days a year · 114 in the 1940s13days above 30°C a year now (2016–2025) · 2 in the 1940sdays above 30°C · 2 in the 1940s+2.8°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 54 mmhigh 1°low −4°February, rain 54 mmhigh 3°low −3°March, rain 57 mmhigh 8°low 0°April, rain 68 mmhigh 14°low 4°May, rain 95 mmhigh 18°low 9°June, rain 105 mmhigh 22°low 12°July, rain 114 mmhigh 24°low 14°August, rain 92 mmhigh 24°low 14°September, rain 74 mmhigh 19°low 10°October, rain 56 mmhigh 14°low 6°November, rain 63 mmhigh 7°low 2°December, rain 58 mmhigh 3°low −2°wettest month July, 114 mm · 890 mm a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Overcast

Right now

21.4°

19°feels like
45%humidity
9°dew point
13 km/hfrom S
UV index2.1
sunrise07:18sunset17:44day length10h 26m
TodayOvercast22°8°
ThuLight rain12°7°
FriClear15°5°
SatOvercast13°7°
SunOvercast16°4°
MonPartly cloudy12°6°
TueClear11°1°

On this date: October 21

Today (forecast)
22° / 8°
Average for October 21
12° / 5°

High well above average · +9.2°C

  • Highest since 1940: 23.2° · 2019
  • Lowest since 1940: −2.4° · 1947
  • One year ago: 14° / 6°

Every October 21 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 21 on record (n = 86). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for Ostrava is sampled from the ECMWF ERA5 reanalysis at 49.83°N, 18.28°E, with daily records since 1940.

Coordinates
49.83°N, 18.28°E
Time zone
Europe/Prague
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

18 of the last 30 days were warmer than the historical average for that date. Average difference: +0.7°C.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

July brings the year's peak warmth, with afternoons typically reaching 23.6°C and nights around 13.9°C. In January, the coolest month, afternoons reach about 0.8°C and nights dip to −4.3°C.

Ostrava picks up roughly 890 mm a year, with a peak of 114 mm in July and as little as 54 mm in February.

The record here starts in 1940, and since then the annual mean in Ostrava has climbed 2.8°C from the first ten years to the last ten. Frost days have thinned out, from around 115 a year in the first decade to about 65 now.

Climate graph (climograph)

July is the warmest month, January the coolest: a yearly swing of 21°C. Wettest month: July (~114 mm). Whole year averages ~890 mm of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 118 rainy days a year: most in June (~12), fewest in October (~7).

Bars = average number of days with ≥ 2 mm per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

Ostrava month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January0.8°−4.3°54 mm98.3 h13.6° (2023)−28.1° (1940)
February2.8°−3.2°54 mm99.8 h17.9° (2021)−27.1° (1956)
March7.6°−0.1°57 mm911.6 h23.7° (1974)−21.1° (1986)
April13.6°4.4°68 mm1013.5 h28.8° (2012)−12.5° (1944)
May18.4°8.8°95 mm1215.2 h31.6° (2005)−2.7° (1980)
June21.7°12.2°105 mm1216.1 h34.1° (2022)1.5° (1977)
July23.6°13.9°114 mm1215.7 h36.2° (2007)5.7° (1964)
August23.5°13.6°92 mm1014.3 h37.6° (2013)5.0° (1976)
September19.3°10.2°74 mm912.4 h34.4° (2015)−1.4° (1970)
October13.8°6.1°56 mm710.5 h27.6° (1942)−8.7° (1950)
November7.2°2.2°63 mm98.8 h21.0° (2008)−18.0° (1975)
December2.6°−1.8°58 mm97.9 h15.4° (1989)−26.9° (1996)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +2.8°C.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.33°C per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Dec–Feb is warming fastest: +0.53°C per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 30°C per year: 2.1 early in the record → 12.9 recently. Frost days: 114 → 65.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2013, coldest in 1940: 37.6°C / −28.1°C.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~890 mm/year on average. Last decade: +6% vs that average. Long-term trend: +16 mm per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about Ostrava

Which is the warmest month in Ostrava?
On long-term average, the warmest month in Ostrava is July (mean daily temperature of about 19.0°C) and the coolest is January (about −1.6°C).
How does today's temperature in Ostrava compare to the historical average?
On October 21, 2026, Ostrava is forecast to reach a high of 21.7°C and a low of 7.5°C. The long-term average for this date (the full record since 1940) is a high of 12.5°C and a low of 5.0°C, so today's high is 9.2°C warmer than that average.
How much has Ostrava warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Ostrava is about 2.8°C warmer.
How much does it rain in Ostrava?
Ostrava receives about 890 mm of precipitation per year on long-term average, with July typically the wettest month.
What is the average temperature in Ostrava?
Over the full record (since 1940), the annual mean temperature in Ostrava is about 9.2°C. The warmest month is July and the coolest is January.
What are the average temperatures in Ostrava by month?
Average daily highs and lows for each month in Ostrava (°C, full record since 1940): January 1°/−4°, February 3°/−3°, March 8°/0°, April 14°/4°, May 18°/9°, June 22°/12°, July 24°/14°, August 24°/14°, September 19°/10°, October 14°/6°, November 7°/2°, December 3°/−2°.
What is the weather like in Ostrava in summer?
Summer in Ostrava (June to August) is wet and pleasantly warm. Daytime highs sit at 22–24°C and nights at 12–14°C; July is the warmest month. Rain is steady at around 104 mm a month, spread over roughly 11 days. No season is wetter.
What is the weather like in Ostrava in winter?
In winter, December through February, Ostrava is cold. Afternoons run 1–3°C and nights −4 to −2°C; January is the coldest month. Rain and snow fall on about 9 days a month, adding up to around 55 mm.
What is the weather like in Ostrava in spring?
March to May is spring in Ostrava, and it is cool. March starts at 8°C by day and 0°C at night; by May it is 18°C and 9°C. Rain rises from 57 mm on 9 days in March to 95 mm on 12 days in May.
What is the weather like in Ostrava in autumn?
Autumn in Ostrava (September to November) is cool. September still brings 19°C afternoons and 10°C nights, November only 7°C and 2°C. Rain falls on about 8 days a month, adding up to around 64 mm.
How many days a year does it rain in Ostrava?
On long-term average, Ostrava has about 118 days a year with at least 2 mm of rain or snow. The annual total is roughly 890 mm.

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